Incidence of vena cava thrombosis in the United States.

From 1979 through 2005, vena cava thrombosis (either superior or inferior) was diagnosed in 99,000 hospitalized patients. Most, 78%, had isolated vena cava thrombosis. From 2000 to 2005, 5,000 patients were diagnosed yearly with vena cava thrombosis (1.5% of patients hospitalized with deep venous thrombosis). The population-based incidence of diagnosis of vena cava thrombosis from 2001 to 2005 was 1.7 in 100,000. The incidence increased with age. It was rare in Asian Americans. Pulmonary embolism occurred in 12% of patients with isolated vena cava thrombosis. Cancer was frequently associated with vena cava thrombosis (37.5%). Among all patients hospitalized with cancer, however, it was an uncommon complication (0.07%). In conclusion, isolated vena cava thrombosis is an uncommon cause of pulmonary embolism but may be considered if the veins of the extremities show no deep venous thrombosis.